Stretching tool



July 29. 1924.

A. s. e. GUENTHER STRETCHING TOOL Filed June 9, 1920 2 Sheets-Sheet 1 Patented July 29, 1924.

rrse STATES 1,503,232 PATENT OFFICE.

ARTHUR G. GUENTI-IER, OF CHICAGO, ILLINOIS, ASSIGNOR TO SIGNODE SYSTEM, INCL, CHICAGO. ILLINOIS. A CORPORATION OF. DELAWARE.

STRETCHING TOOL.

Application filed June 9,

To all whom it may concern z Be it known that I, ARTHUR G. G. GUENTHER, a citizen of the United States, and resident of. Chicago, in the county of 6 Cook and State of Illinois, have invented a certain new and useful Improvement in Stretching Tools, of whichthe following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification. a This invention relates to tools for use in applying tensional binding such as flat metallic tensional box strapping to boxes and packages. It is the object of the invention to provide a stretching tool of simple .and economical construction eflicient in operation, by which box strapping or the like may rapidly and efficiently be stretched or tightened about a box or package.

In the drawings which represent an illustrative embodiment of the invention:

Fig. 1 is a side elevation of the tool. Fig. 2 is a plan view thereof. Fig. 5 is a cross sectional view of the line -33 of Fig. 4.

Fig. 4 is an enlarged elevation of one of the gripping jaws of the tool.

Referring to Fig. 1 the tool is there shown in its position as seated upon a box or package ready for the stretching operation. The tool is provided with a pair of automatic gripping jaws 1 whose particular construction will later be described. These jaws are off-set laterally from and slidable upon an elongated base 2. At its center portion the base is provided with an upstanding toothed segment 3 on which is piv-- otally mounted an operating handle 4. Links 5 connect points in the operating handie, at opposite sides of its pivot, with the gripping jaws 1 so that a movement of the operating handle to the right serves to draw the two gripping jaws 1 together. taining dog 6, provided with a release spring controlled thumb piece 7 maintains the handle 4 in position against the tension of the straps, by engagement with the toothed segment 3. It will be understood that assuming the tool shown in Fig. 1 to be seated upon a box or package, the ends of a metallic binder surrounding the box, or package, are engaged in the grippingjaws 1, the movement of the handle 4 to the. right,

Are-

(Fig. 1) will serve to pull these ends to- 1920. Serial No. 387.768.

segment with a rail 10; the rail 10 is interrupted at the central portion of the base in orderto make room for the operating parts. Upon the rail 10 slide the two carriages 11 (Fig. 3) having flanges 12 and 13 engaged in the grooves of the rail 10 and the flange 14 engaged over the rear corner of the base 2. In the form shown, each carriage 11 is made up of a solid block 15 and a top plate .16' secured thereto by the screws 17 At the forward or free end of the carriages 11. means are provided for mounting the gripping mechanism 1 previously alluded to. Thus the free end of the blocks 15 are recessed, as shown at 18, and provided with a rib 19. Slidably mounted in the recess and grooved for engagement with the rib 19 is a wedge block 20, secured in place by the plate 21 having a rib 22 opposite the rib 19 and similarly engaged in a groove in the wedge block. The ribs 19 and 22 are inclined downwardly from right to left (Fig. 4) as is the top of the recess 18 which forms the backing for the top of the wedge block 20. The wedge block 20 is provided with a flat, toothed, lower face 23 which co-operates with the flange 24 which forms the bottom of the recess 18. The upper face of this flange is inclined so as to provide a narrower opening on the side toward the center of the tool than'toward the end.

Box strapping, or the like, introduced from left to right in the gripping mechanism shown'in Fig. 4 will be engaged thereby, between the wedge block 20 and the flange 24, with an engagement which be-' comes tighter as the carriage is moved to the right, Fig. 4, but which may instantly be released by moving the carriage in the opposite direction if the box strap is meanwhile held stationary. a

I shall now describe the means for mov- 110 ing the gripping mechanism toward each other. The lip-standing segment 3, is provided with a bolt 28 nponwhich is pivotally mounted the fork 29 forming a part. of the handle 4. Upon both branches of the fork 29 and equally spaced on opposite sides of the bolt 28 are pins 30 upon which are pivoted the links 5. These links at their other ends are pivoted to the carriage 11, being journalled on a pin 31 which is mounted in whose 32 upon the top plate 15 of each carriage; Cotter pins 33 serve to hold the pins ill in place.

In operation the device being positioned on a box or package with the grippers in the line upon which it is desired to apply a binding to the box or package, the ends of the binder are thrust from opposite directions through the grippers (i. e. through the space between'the wedge block 20 and the flanges 24) projecting somewhat beyond the grippers as shown at 35 (Fig. 2). Thereafter the handle 4 is moved from left to.

right Fig. 1 which action by a single quick motion draws the strap taut around the box or package and causes its ends to overlap as shown in dotted lines, Fig. 2. The dog 6 meanwhile automatically engages with the toothed segment 3, to maintain the strap in tension with its ends overlapped upon the box. A joint may now be formed between the overlapped box strap ends, after which the dog 6 is released by means of the thumb piece 7, and the handle 4 restored to its original position. This movement will push the two grippers apart, and since the strap ends cannot slide back with the grippers because now connected to each other at the joint, the wedge blocks must release their engagement with the strap whereupon the tool can be slipped sideways to clear the strap, and removed.

Any desired degree of tension may be developed by the tool in accordance with the force applied by the operator and the length of the handle & employed. The gripping mechanism is automatic and requires no adjustment or manipulation. The strapping operation is performed at a single stroke, similarly the releasing operation merely requires one reverse movement of the lever after which the tool may be removed from the box.

I claim:

1. In apparatus of the class described, and in combination a base, a pair of grippers mounted thereon, each adapted to be engaged with a box strap end sliding connections between said base and each of said grippers, respectively. a lever, and direct connections between the lever and the grippers wherebysimultaneous equal movement ol the grippers result from the operation of the lever. i

2. In apparatus of the class described, and in combination, a base, a pair of grippers slidably mounted thereon: a lever pivoted on the base, connections between the lever and the grippers, said connections being applied to the lever on opposite sides of the pivot thereof.

In apparatus of the class described, and in combination, a base, a pair of grippers slidably mounted thereon, but oil-set horizontally from the base to provide a clearance, a lever pivoted 0n the base and relatively oil-set horizontally from the grippers, and direct action connections from said lever to said grippers.

4. In apparatus of the class described, and in combination, a base, automatic grippers adapted to engage a box strap end or the like, slidably mounted on theqbase for movement toward or away from each other, a lever mounted on the base and connected directly with the grippers whereby the in sertion of strap ends in the grippers, and a single stroke of the lever, will stretch the strap about a box or package.

5. In apparatus of the class described, and in combination, a base, automatic grippers adapted-to engage a box strap end or the like, mounted movably on the base for movement toward or away from each other, a lever mounted on the base and connected directly with the grippers, said grippers 

